The present invention relates generally to user adjustment of input parameters for a system having a display and a cursor control device, and more particularly to user adjustment of graphical control elements in a graphical user interface.
Some electronic devices are controlled by entering text commands on a keypad on the device or a keyboard connected to the device. It may be difficult for a user to remember all of the text commands needed to operate an electronic device, the syntax of each command, and the best command to use for a particular operation. Furthermore, typing a string of text characters to enter a command into an electronic device is subject to typing errors and may divert a user's attention from other, more urgent or more important matters. For example, persons who interact with complex process control systems by entering text commands into keyboards may concentrate so intently on entering commands correctly that they fail to notice that the process or system they should be monitoring is not performing optimally.
A user may prefer to interact with an electronic device by adjusting graphical control elements presented on a display rather than by entering text commands into a keyboard or keypad. A user interface which includes graphical control elements on a display is sometimes referred to as a graphical user interface (GUI). Changing a graphical control element in a GUI may cause corresponding changes in a system parameter associated with the graphical control element. A user of an electronic device with a GUI need not remember the underlying system commands the GUI outputs to control the electronic device. A GUI may be arranged so that only those graphical control elements related to a particular operation are visible at one time on a display, making it simpler for a user to learn and remember how to interact with an electronic device.
A cursor control device such as a mouse, touchpad, trackpad, multidirectional cursor key, touch input system on a display, digitizing tablet, or joystick may be used to select and modify a graphical control element in a GUI. To adjust an input parameter associated with a graphical control element, it may be necessary to use the cursor control device to precisely position a cursor over or in close proximity to a selected graphical control element. For example, in some systems, it is necessary for the outer perimeter or outline of the cursor to at least partially overlap the outer perimeter or outline of the selected graphical control element. Then, pressing a button on the cursor control device, often referred to as “clicking”, selects the graphical control element for adjustment. Further motion of the cursor control device, sometimes referred to as “dragging”, causes a corresponding adjustment of the graphical control element and its corresponding system parameter. Sometimes clicking and dragging are performed simultaneously to adjust a graphical control element. Another “click” may be required to deselect the graphical control element and disassociate further motion of the cursor control device from the graphical control element.
Adjusting a graphical control element by clicking and dragging part of the element is relatively simple when the graphical control elements are large enough and spaced far enough apart to enable a user to quickly and easily select an element with a cursor control device. However, in some systems it may be preferable to view many graphical control elements at the same time so that relationships between individual parameter settings may easily be observed or so that related parameters may be set quickly without paging from one display screen to another. Presenting too many graphical control elements simultaneously on one display may cause the graphical control elements to be so small that it becomes difficult to manipulate a cursor control device precisely enough to select and adjust each graphical control element. Partitioning a related set of graphical control elements onto more than one screen image so that each graphical control element is large enough to view and control easily may require a user to move from one screen image to another by paging or scrolling. Paging or scrolling to view and operate graphical control elements may be inconvenient, slow, cause user confusion, or may have other undesirable effects on user interactions with an electronic device. Locating graphical control elements on pop-ups or pull-downs or resizing graphical control elements with twisties or other resizing controls may also interfere with a user's interactions with a GUI.